Talks between rival Libyan institutions aimed at breaking the deadlock over the rules for long-awaited elections failed to resolve key differences, the United Nations said Thursday. Parliament speaker Aguila Saleh and President of the High Council of State Khaled Al-Mishri met at the UN in Geneva for three days of talks to discuss the draft constitutional framework for elections. But while some progress was made, it was not enough to move forward towards national polls, with the two sides still at odds over who can stand in presidential elections, said the UN’s top Libya envoy Stephanie Willia…